All fish / Melanotaeniidae

Lake Wanam rainbowfish

Glossolepis wanamensis

Also known as wanam rainbowfish, lake wanam rainbow, wanamensis rainbowfish, glossolepis wanamensis, green rainbowfish, グロッソレピス・ワナメンシス, 瓦南湖彩虹鱼

A deep-bodied rainbowfish from a single lake in Papua New Guinea, with adult males turning a metallic green to golden yellow and growing a pronounced hump with age. It is kept for its bright colour, active shoaling behaviour and its value as a conservation species, as it is thought to be close to extinction in the wild.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

9 cm

Temperature

24 to 29 °C

pH

7 to 8

Smallest tank

200 litres

Keep as

Shoal of 6 or more, with more females than males

Diet

Omnivore: quality flakes and granules, frozen bloodworm, brine shrimp and daphnia, some vegetable matter

Swims

Middle of the tank

Lifespan

5 to 8 years

Water

Freshwater

Wild range

Lake Wanam, Markham River basin, Papua New Guinea

Breeding

An egg scatterer that lays adhesive eggs among fine plants or spawning mops over several days. Breeding is fairly easy: remove the eggs to a separate tank, where they hatch in about a week, and feed the fry infusoria and then baby brine shrimp.

Good to know

Listed as Critically Endangered by the IUCN, so keep captive lines pure and do not mix with other rainbowfish that could hybridise. It needs a long, well-filtered tank and stable, slightly hard alkaline water.